Soap-containing compositions generally need to be protected against decomposition as shown by discoloring, particularly yellowing, of the composition. Such protection usually comes from various opacifying materials present in a soap composition such as titanium dioxide, zinc oxide and the like. However, certain solid soap-containing compositions are desirably translucent or even transparent. Opacifiers and other materials which bring about opaqueness and behave as discoloration inhibitors are absent from these compositions. Therefore, discoloration, particularly yellowing of the solid soap-containing compositions can be a significant issue. Such discoloration can become even more exacerbated when the container has at least one window through which the translucent or transparent soap bar can be visualized by the human eye, or the entire container is made from a material through which the translucent or transparent soap bar can be viewed.
Such discoloration of a transparent or translucent soap bar has now been essentially overcome through use of an antidiscoloring effective quantity of a specific benzotriazole of the hydroxyphenylbenzotriazole class, namely 2-(5-chloro-2H-benzotriazole-2-yl)-6-(1,1-dimethyl)-4-methyl-phenol (CAS No. 3896-11-5) and CTFA name of Bumetrizole.